Compact imaging optics using liquid crystal (lc) for dynamic glare reduction and sharpness enhancement

Abstract

An optical assembly to reduce glare and enhance sharpness in a head-mounted device (HMD) is provided. The optical assembly may include an optical stack, such as pancake optics. The optical assembly may also include at least two optical elements. The optical assembly may further include at least one liquid crystal (LC) layer between the at least two optical elements, wherein the liquid crystal (LC) layer provides dynamic glare reduction and enhanced sharpness using a controllable polarization technique. In some examples, the controllable polarization technique may include determining optical assembly orientation using a sensor. Based the optical assembly orientation, the polarization of the at least one liquid crystal (LC) layer may be dynamically adjusted via adjustments in applied voltage to minimize or reduce glare and enhance visual sharpness.

1 . An optical assembly, comprising:
 an optical stack comprising at least two optical elements; and   at least one liquid crystal (LC) layer between the at least two optical elements, wherein the liquid crystal (LC) layer provides dynamic glare reduction and enhanced sharpness using a controllable polarization technique.   
     
     
         2 . The optical assembly of  claim 1 , wherein the optical stack comprises pancake optics. 
     
     
         3 . The optical assembly of  claim 1 , wherein the at least one liquid crystal (LC) layer is a liquid crystal (LC) cell comprising at least one a nematic liquid crystal (LC) cell, a nematic liquid crystal (LC) cell with chiral dopants, a chiral liquid crystal (LC) cell, a uniform lying helix (ULH) liquid crystal (LC) cell, a ferroelectric liquid crystal (LC) cell, or electrically drivable birefringence material. 
     
     
         4 . The optical assembly of  claim 1 , wherein the controllable polarization technique comprises:
 determining optical assembly orientation using a sensor; and   dynamically adjusting polarization of the at least one liquid crystal (LC) layer based on the determined optical assembly orientation.   
     
     
         5 . The optical assembly of  claim 1 , wherein the controllable polarization technique is based on at least user input. 
     
     
         6 . The optical assembly of  claim 1 , wherein the at least one at least one liquid crystal (LC) comprises a plurality of zones so that polarization in each of the plurality of zones is controlled and adjusted separately from each other. 
     
     
         7 . The optical assembly of  claim 1 , further comprising:
 a cover window for the at least one liquid crystal (LC) layer.   
     
     
         8 . The optical assembly of  claim 7 , wherein the cover window is curved causing the at least one liquid crystal (LC) layer to function as an optical lens. 
     
     
         9 . The optical assembly of  claim 1 , wherein the optical assembly is part of a head-mounted display (HMD) used in at least one of a virtual reality (VR), augmented reality (AR), or mixed reality (MR) environment. 
     
     
         10 . A head-mounted display (HMD), comprising:
 a display element to provide display light; and   an optical assembly to provide display light to a user of the head-mounted display (HMD), the optical assembly comprising:
 an optical stack comprising at least two optical elements; and 
 at least one liquid crystal (LC) layer between the at least two optical elements, wherein the liquid crystal (LC) layer provides dynamic glare reduction and enhanced sharpness using a controllable polarization technique. 
   
     
     
         11 . The head-mounted display (HMD) of  claim 10 , wherein the optical stack comprises pancake optics. 
     
     
         12 . The head-mounted display (HMD) of  claim 10 , wherein the at least one liquid crystal (LC) layer is a liquid crystal (LC) cell comprising at least one a nematic liquid crystal (LC) cell, a nematic liquid crystal (LC) cell with chiral dopants, a chiral liquid crystal (LC) cell, a uniform lying helix (ULH) liquid crystal (LC) cell, a ferroelectric liquid crystal (LC) cell, or electrically drivable birefringence material. 
     
     
         13 . The head-mounted display (HMD) of  claim 10 , wherein the controllable polarization technique comprises:
 determining optical assembly orientation using a sensor; and   dynamically adjusting polarization of the at least one liquid crystal (LC) layer based on the determined optical assembly orientation.   
     
     
         14 . The head-mounted display (HMD) of  claim 10 , wherein the controllable polarization technique is based on at least user input. 
     
     
         15 . The head-mounted display (HMD) of  claim 10 , wherein the at least one at least one liquid crystal (LC) comprises a plurality of zones so that polarization in each of the plurality of zones is controlled and adjusted separately from each other. 
     
     
         16 . The head-mounted display (HMD) of  claim 10 , further comprising:
 a cover window for the at least one liquid crystal (LC) layer.   
     
     
         17 . The head-mounted display (HMD) of  claim 10 , wherein the cover window is curved causing the at least one liquid crystal (LC) layer to function as an optical lens. 
     
     
         18 . A method for providing dynamic polarization in an optical assembly, comprising:
 providing at least one liquid crystal (LC) layer between two optical components of an optical assembly; and   adjusting, using a controllable polarization technique, one or more zones of the at least liquid crystal (LC) layer to provide dynamic glare reduction or enhanced sharpness.   
     
     
         19 . The method of  claim 18 , wherein the at least one liquid crystal (LC) layer is a liquid crystal (LC) cell comprising at least one a nematic liquid crystal (LC) cell, a nematic liquid crystal (LC) cell with chiral dopants, a chiral liquid crystal (LC) cell, a uniform lying helix (ULH) liquid crystal (LC) cell, a ferroelectric liquid crystal (LC) cell, or electrically drivable birefringence material. 
     
     
         20 . The method of  claim 18 , wherein the controllable polarization technique comprises:
 determining optical assembly orientation using a sensor; and   dynamically adjusting polarization of the at least one liquid crystal (LC) layer based on the determined optical assembly orientation,   wherein each of the one or more of zones is controlled and adjusted separately from each other, and wherein the at least one liquid crystal (LC) layer is configured to operate as a polarizer or an optical lens.